Clam-shell bucket.



N. P. E. ANDERSEN. OLA M SHELL BUCKET. APPLICATION FILED JUNE 27I 1913.

Patented May 12, 1914.

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ClJI-UMBIA PLANOGIAPM CO.. wAsmNu'rorg. D. :4

N. P. B. ANDERSEN.

GLAM SHELL BUCKET.

APPLIOATION FILED mm: 27, 1913.

1,096,214. Patented May 12, 1914 3 SHEETS-SHEET 2.

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N. P. E. ANDERSBN.

GLAM SHELL BUGKET.

APPLICATION FILED JUNE27, 191s.

Patented May 12, 1914.

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cOl-UMBIA PLANOGRAI'H C0., WASHINGTON, III-C.

U N ITED STATES PATENT OFFICE.

NILS P. E. ANDERSEN, 0F MILWAUKEE, WISCONSIN, ASSIGNOR TO PAWLING AND HARNISCHFEGER COMPANY, OF WEST MILWAUKEE, WISCONSIN, A CORPORATION OF WISCONSIN.

CLAM-SHELL BUCKET.

To all whom it may concern Be it known that I, NlLs P. E. ANDERSEN, a citizen of the United States, residing at Milwaukee, in the county of Milwaukee and State of Visconsin, have invented certain new and useful Improvements in Clam-Shell Buckets, of which the following is a specification, reference being had to the accompanying drawing, forming a part thereof.

This invention relates more particularly to so called single rope buckets, or such as are closed and lifted by the same rope.

The main objects of the invention are to prevent shocks incident to the operation of the bucket and consequent injury to the bucket and the hoisting apparatus with which it is connected, aswell as danger to operators and attendants, and generally to improve the construction and operation of buckets of this class.

It consists in the construction, arrangement and combination of parts, and more particularly in an automatically adjustable stop for separating the lifting and closing heads more or less and preventing them from being brought violently together when the bucket is opened in case it has not been fully closed, as when an obstruction is caught between the scoops, and in improved means for guiding and holding the coupling member carried by the scoops in proper position for engagement with the other coupling member carried by the closing head to whatever extent the bucket may be opened and in whatever position the scoops may rest when the closing head is lowered relatively thereto and to the lifting head.

In the accompanying drawing like characters designate the same parts in the several figures.

Figure 1 is a side elevation of a bucket embodying the invention, the bucket being shown in its open position; Fig. 2 is an end elevation of the bucket closed, as viewed from the right relative to Fig. 1; Fig. 3 is a section the plane of which is generally inclicated by the line 33, Fig. 2, of the bucket closed; Fig. 4 is a similar section of the lifting and closing heads, showing the trip lever and adjustable stop in different positions; and Fig. 5 is a section on the line 55, Fig. 2, showing the opposite side of the adjustable stop.

The bucket comprises a pair of scoops 1, provided with hinge plates or arms 2, which Specification of Letters Patent.

Application filed June 27, 1913.

Patented May 12, 1914. Serial No. 776,080.

are pivotally connected by pins 3, with each other and with a sleeve or cross head 1. The scoops are pivotally suspended by links 5) and 6 from a lifting head 7 which may be cast or formed integrally with the upper ends of the links 5 and which forms a housing or support for sheaves 8 and 9 for the operating rope 10. The links 5 and 6 are pivotally connected adjacent to their upper ends by a pin 11, and the links 5 and 6 are extended upwardly beyond the pin 11 and connected by a pin 12 which passes through slots 13 in the sides of the head 7. The sheaves 8 are mounted within and next to the sides of the head 7 on a pin 14, which is held at its ends in the sides of the head, and the sheave 9 is pivotally suspended by a hanger 15 from the pin 12 transversely to the sheaves 8 and on the opposite side of the pin 11 therefrom.

A trip lever 16, fulcrumed on the pin 14 between the sheaves 8, has an upwardly projecting arm 17, which is connected by a retracting spring 18 with the head 7. A slotted trip bar 19, guided on a cross pin 20, which is secured at its ends in the sides of the head 7, is pivoted at its upper end to the lever 16, and projects at its lower end into the path of a latch hereinafter described.

To separate the lifting head 7 from the closing head hereinafter described, more or less, and to prevent injurious shocks to the bucket and the hoisting apparatus from which it is suspended by the heads being brought violently to ether when the bucket is tripped and opene in case the scoops are separated more or less by obstructions, such as rocks, blocks of wood or the like, the bucket is provided with a selfadjusting tapering or graduated stop. This stop, which may be constructed in various ways to fill the variable space between the heads according to the degree of separation of the scoops by 0b structions in closing the bucket, as shown in the present case, comprises a segmental or curved support or bearing 21, mounted on the pin 11, and a tapering shoe or wedge 22, slidably mounted on said support or hearing and yieldingly connected with the trip lever 16. The support or bearing 21, the curved working face of which is concentric with the pin 11, is held against turning on said pin by the pin 14 engaging a notch in 1ts periphcry. The tapering shoe or wedge 22, which loosely fits over and embraces the curved periphery or working face of the support or hearing 21, is extended on one side thereof and journaled on the pin 11.

The recess in the shoe or wedge fitting over the periphery of the segmental support or bearing, is preferably provided as shown, with a lining 23, of thermoid or other suitable tough friction material. A rod 24 is pivoted at one end to the shoe or wedge 22, and passes loosely through a swivel pin 25 in the forked arm of a lever 26, mounted on the pin 14, on the opposite side of the support or bearing 21 from the lever 16, with which it is connected by a pin 27. The rod 24 is provided at its outer end with a stop nut or head 28, and a spring 29, surrounding the rod between a collar or shoulder thereon and the swivel pin 25, tends to hold the shoe or wedge and the lever 26 as far apart as said rod and its stop nut or head will permit. The lever 26 constitutes in effect a part of the trip lever 16, being separated therefrom by the intervening segmental support or hearing 21. The support or bearing 21 is provided on one side thereof as shown in Fig. 5, with a stop pin or lug 30 for limiting the backward movement of the shoe or wedge 22 toward the trip bar 19.

The scoop suspending links 5 are formed or provided at their lower ends with upwardly and outwardly extending arms 31, with the upper ends of which a forked radius or guiding arm 32 is pivotally connect ed. At its inner free end the arm 32 is formed or provided with a head 33, designated as the closing head, in which a hook 34 is pivotally mounted on a cross pin 35, parallel with the pivot pins 3 in the sleeve or cross head 4 and with the pin 11 in the lifting head 7. At the sides of the head 33, sheaves 36 are mounted on the protruding ends of the pin 35 between spaced guard plates 37, which are bolted or riveted to the sides of said head.

In the forked shank of the hook 34, projecting outwardly from the opposite side of the pin 35, a latch 38 is pivoted on a pin 39. A pin 40, secured at its ends in the shank of the hook, passes through a curved slot in the latch, and between the pin and one end of the slot a spiral spring 41 is confined in the slot. This spring normally holds the inner end of the latch in working position opposite the bight of the hook, as shown in Fig. 3. The latch 38 has a striking plate 42 projecting outwardly therefrom into line with the trip bar 19.

The nose of the hook, is heavier than the shank and the latch 38, so that when released it will be turned by gravity into engaging position, and is rounded or beveled so that it will be guided automatically into engagement with the other member of the coupling, and the hub of the hook is formed or provided With a lug 43, which by engagement with a projection 44 on the under side of the head 33, limits the downward movement of the nose in proper position to engage with the other member of the coupling. The head 33 is formed on the upper side in line with the stop shoe or wedge 22 with a rounded lug or hearing face 45.

Between upwardly projecting cars 46 on the sleeve or cross head 4, a roller- 47 is mounted on a pin 48, in position to co5perate with the hook 34, to connect the head 33 with the sleeve or cross head 4, for closing the bucket. The roller 47 is guided and held in position for engagement with the hook 34 to whatever extent the bucket is opened, by an inverted U-shaped yoke 49, slidably fitted on a squared end 50 of the sleeve or cross head 4 and connected by curved links 51 with the adjacent hinge plates or arms 2 of the scoops on opposite sides of and equidistant from the axis of the pivot pins 3. This guiding connection holds the pin 48 in the same plane with the pins 3 and 11 in whatever position the sleeve or cross head 4 may be relative to the lifting head 7. To prevent the material with which the bucket is loaded from interfering with the operation of the hook 34, guards 52 are riveted to flanges on opposite sides of the sleeve or cross head 4, or are otherwise attached thereto.

The links 5 and the links 6 are preferably cast or formed at their lower ends with arched or channeled cross pieces 53 and are pivotally connected with the scoops 1 by rods 54 passing through said cross pieces and secured at the ends in the hinge plates or arms 2. The branches of the radius arm 32 are also preferably cast or formed integrally with an arched or channeled cross piece 55 at their outer ends, and are pivotally connected with the arms 31 by a rod 56.

The opening and closing movements of the scoops are checked by pneumatic shock absorbers each consisting of a cylinder 57 and a plunger 58, pivoted at their outer ends to arms 59, riveted or otherwise fastened to the hinge plates or arms 2, and extending upwardly and outwardly from the upper and outer parts of the scoops when the bucket is closed, as shown in Fig. 3. The plunger 58, which has a sliding fit in the associated cylinder 57, is provided with one or more cup leathers or packings (30, which tend to spread and prevent the passage of air between the plunger and cylinder when the plunger is moved into the cylinder, but contact when the plunger is withdrawn, there by allowing air to pass into the closed end of the cylinder and permitting the scoops to turn freely relative to each other in the fore part of both the closing and the opening of the bucket.

Adjacent to its closed end each cylinder has a vent hole 61 as shown in Fig. 1, which permits sufiicient freedom and rapidity of movement to the scoops in the latter part of both the opening and the closing of the bucket. At the limit of their opening movement the scoops are positively stopped by the engagement of a projection 62 on the plunger with the cylinder head.

The operating rope 10, which is connected with the hook of a crane or other hoisting device, passes through openings in the top of the head 7 around the inner sides of the guiding sheaves S, thence downwardly around the sheaves 36 carried by the closing head 33, and thence upwardly around the sheave 9 in the lifting head, the sheave 9 serving as an evener to equally distribute the load on both stretches of the rope by which the bucket is suspended. The lifting and closing heads may be provided with more or less sheaves to multiply more or less the lifting power exerted on the rope for closing the bucket. lVith the arrangement shown the force exerted by the rope on the head 33 to close the bucket is doubled.

In the operation of the bucketafter it has been opened or discharged, it is lowered to the ground or floor from which a load is to be taken up, in the position in which it is shown in Fig. 1, the head 33 being held up by the rope 10 against the head 7 or the stop shoe or wedge 22, until the scoops are brought to rest on the ground or floor. The rope 10 is then paid out or slackened till the head 33 descends into the position indicated by dotted lines on Fig. 1, and the hook 34 engages with the roller 47, the latch 38 yielding upwardly against the tension of the spring -11 to permit the roller to pass into the bight of the hook and then dropping behind the roller and locking the hook in engagement therewith, as shown in Fig. 3. The rope 10 being wound and drawn up by the drum of the crane or hoist, operates first to draw the head 33 up to the head 7 thereby lifting the sleeve or cross head 4: to which the scoops are pivoted and closing the bucket, the scoops scraping up and gathering the load as they are drawn together. After the bucket has been thus closed, the further pull on the rope lifts it with its load. In case an obstruction, such as a rock or block of wood, is caught between the scoops, and the bucket is thereby prevented from completely closing, the lug or bearing 45 on the head 33 will not be carried up into contact with the stop shoe or wedge 22, but a space will be left between them of greater or less extent according to the degree of separation of the scoops while the bucket is being lifted. To release, open and discharge the loaded bucket after it has been lifted to the desired extent, the outer end of the trip lever 16 is pulled downward by a rope attached thereto for the purpose, thereby thrusting the bar 19 downward against the striking plate 42 on the latch 38, and throwing the inner end of the latch upward out of engagement with the roller 47. The roller being thus released, rolls off from the inclined bight of the hook, which swings upwardly and outwardly out of its way, and the sleeve or cross head 4 drops, the pivot rods 54 swinging first outwardly and then inwardly, till the scoops reach their open position, as shown in Fig. 1. As the rods 54: approach each other during the latter part of the opening movement of the scoops, the plungers 58 are thrust into the cylinders 57, thereby compressing the air confined in the closed ends of the cylinders and checking the movement 'of the scoops till it is positively arrested by the engagement of the projections 62 on the plungers with the cylinder heads, without shock to the bucket or the hoisting device from which it is suspended. In case the bucket is not completely closed when it is tripped by the downward pull on the lever 16, the stop shoe or wedge 2 is yieldingly thrust forward by the pressure of the swivel pin 25 against the spring 29, to fill the gap between said shoe or wedge and the lug 45 on the head 33, as shown in Fig. 1, so that when the roller at is disengaged from the hook 34 and the weight of the bucket and its load are shifted to the lifting head 7, the heads cannot be brought violently together by the pull on the rope, and shock and injury to the bucket and the hoisting apparatus, as well as danger to attendants, are avoided. Then the trip lever 16 is released by the operator and the stop shoe or wedge 22 is relieved from pressure against the head 33, they will be returned by the spring 18 to their original positions as shown in Fig. 3. If the bucket is completely closed when it is tripped and opened the point or narrower part of the tapering shoe or wedge 22 will be gripped and held between the segmental support or bearing 21 and the projection 15 on the head 33, as shown in Fig. 1, the spring 29 being compressed to a greater extent to permit the operatlon of the trip lever 16 for disengaging the latch 38 from the roller 17 Various modifications in the details of construction and arrangement of parts may be made without materially affecting the operation of the bucket and without departing from the principle of the invention as defined in the following claims.

I claim:

1. In a clam shell bucket the combination with pivotally connected scoops, a lifting head connected with the scoops, a closing head having a guiding connection with one of the scoops, means for detachably coupling the closing head with the scoops, an operating rope connected with said heads for closing and lifting the bucket, and means for releasing said coupling means to open the bucket, of an automatically adjustable graduated stop adapted when the scoops are released and separated in opening the bucket to unyieldingly separate and hold. said heads apart, according to the degree of separation of the scoops by obstructions in closing.

2. In a clam shell bucket the combination with pivotally connected scoops, lifting and closing heads connected with the scoops, means for detachably coupling the closing head with the scoops, an operating rope connecting said heads, and a trip lever carried by the lifting head for releasing the coupling means and opening the bucket, of an adjustable stop yieldingly connected with said trip lever and adapted to limit the approach of the closing head to the lifting head and to prevent their coming violently together when the bucket is opened if the scoops are separated more or less by obstructions.

3. In a clam shell bucket the combination with pivotally connected scoops, relatively movable lifting and closing heads connected with the scoops, means for detachably coupling the closing head with the scoops, an operating rope connecting said heads, and a trip lever carried by the lifting head for releasing the coupling means and opening the bucket, of an adjustable stop for limiting the approach of said heads to each other, comprising a bearing fixed to the lifting head, a wedge slidably mounted on said bearing, a rod connecting the wedge with an arm of the trip lever and having a slip connection with one of said parts and a compression spring interposed between said wedge and arm.

4. In a clam shell bucket the combination with pivotally connected scoops, a lifting head, links connecting the scoops with said head, a closing head guided and movable between the lifting head and scoops, means for detachably coupling the closing head with the scoops, an operating rope connect-- ing the heads and adapted to draw them together and close the bucket before lifting it, and a trip lever carried by the lifting head for releasing the coupling means and per mitting the bucket to open, of a stop adapted to separate said heads more or less when the bucket, if not completely closed, is tripped and opened, and comprising a curved bearing piece fixed to the lifting head concentric with the pivot connection between the upper ends of said links, a curved wedge slidably mounted on said bearing and connected by a rod with an arm of the trip lever, a spring interposed between said wedge and arm, and a stop on said bearing for limiting the backward movement of the wedge.

In a clam shell bucket of the class described, the combination of a cross head having a coupling member, scoops pivotally connected with each other and with the cross head, a lifting head connected with the scoops, a closing head guided between the lifting head and the scoops and provided with a coupling member adapted to cooperate with the coupling member on the cross head, a sliding member mounted on the cross head and movable transversely to its axis, and links pivoted at one end to said sliding member and at the other end to the scoops on opposite sides of their pivotal connection with each other.

6. In a clam shell bucket of the class described, the combination of a cross head having a coupling member on the upper side and a squared portion adjacent to one end thereof, scoops pivotally connected with each other and with the ends of the cross head, a lifting head connected by links with the outer parts of the scoops, a closing head having a guiding connection with one of the scoops and provided with a coupling hook arranged to cooperate with said coupling member to close the bucket, a yoke slidably mounted on and embracing the squared portion of said cross head, and links connecting said yoke with the scoops on opposite sides of and equidistant from the line of the pivot connections between the scoops and cross head.

7. In a clam shell bucket of the class described, the combination of a cross head having a coupling pin on the upper side and a squared portion adjacent to one end, scoops pivotally connected with the ends of the cross head, relatively movable lifting and closing heads connected with the scoops, the closing head being provided with a coupling hook adapted to cooperate with said coupling pin for closing the bucket, an inverted U-shaped yoke slidably mounted on the squared portion of said cross head, and curved links pivoted at their inner upper ends to the yoke and at their outer lower ends to the scoops equidistant from the pivot connection between the scoops and cross head.

In witness whereof I hereto afiix my signature in presence of two witnesses.

NILS P. E. ANDERSEN.

IVitnesses CHAS. L. Gross, FRED PALM,

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Eatents, Washington, 1). G. 

